Device for trimming sheet material



May 22, 1956 H. CHAMBERLAIN 2,746,545

DEVICE FOR TRIMMING SHEET MATERIAL Filed Feb. 19, 1951 2 Sheets-Sheet lm 4 26 4 7 I 75 5 W I mi I j j "I" \JQ 7" 7m 4 4M 7 I 5 mm P76. 1 V

attorneys y 2, 1956 G. H. CHAMBERLAIN 2,746,545

DEVICE FOR TRIMMING SHEET MATERIAL Filed Feb, 19, 1951 2 Sheets-g 2 1f d.76 3/ 7 f 1 11M 52 Ml Z5 l ljmm iL Z? 24 57 47 i 24 i29 5/27 5 6/, l 448 \V 75- I g 1 ill I Q 26 Ti 72 17 1 l 2,746,545 r V nnvrcnron TRIMMINGSHEET MATERIAL George H. Chamberlain, San Jose, Calif. ApplicationFebruary 19, 1951, Serial No. 211,763

3 Claims. (Cl. 164 -77) This invention relates to an improved form ofdevice for trimming paper orother sheet material and is related to myco-pending application Serial No. 5,237, filed January 30, 1948, nowPatent No. 2,626,665.

As in the above-noted co-pending application, so here also the inventionrelates to a type of device in which the cutting member hasstraight-line movement along the cutting edge of the board, asdistinguished from the more familiar type of device in which a cuttingblade is pivotally mounted at one corner of the trimmingboard and isadapted to be lowered along the cutting edge of the board with ahinge-like movement. As explained in connection with theabove-notedapplication, this old and familiar type of device has provedto be quite objectionable for various reasons.

As also noted in the aforesaid application, the patent to Silver, No.2,327,223, August 17, 1943, is an instance of later attempts to devise atrimming board in which the trimming element has a straight-linemovement; and it i is this type of device to which mypresentimprovements relate. a

One object of my present invention is to devise a trimming board of thistype in which its cutting capacity is extended without increasing thesize of the board itself,

this feature relating to the particular form and arrangernent of mypresent goose-neck brackets which constitute a still further improvementover those disclosed in my cospending application, supra.

Another object is to devise a trimming board of this type with animproved means for, mounting the rotary cutter assembly upon itscarriage which is adapted for straight-line movement.

.Another object is to devise a trimming board of this type with animproved means for mounting the reversing gear assembly upon thecarriage.

"Another object is'to devise a trimming board of this type with animproved means for mounting the ball bearing elements upon .the carriagefor straight-line movement.

Another object is to devise a trimmer of this type with an improvedmeans for mounting the shear blade upon the edge of the. trimming board.A

transparent scale hinged to the adjustable stop, for align ing marksetc. upon the work beneath.

Another object is to devise a trimmer of this type with animprovedmanner of mounting the carriage upon the rail means for straight-linemovement therealong.

Other objects will appear from the following description and claims whenconsidered together with the accompanying drawings;

, Fig. 1 is a perspective. view of my present invention embodying oneform of bracket supporting means;

ted Stags Patent ice manner of mounting the-shearing blade upon theboard;

Fig. 4 is a view taken on line 4-4 of Fig. 3 and indicates the manner ofmounting the brackets upon an in serted rod in the edge of the board;

Fig.5 is a view taken on line 55 of Fig. 3;

Fig. dis a view corresponding to line 6-6 of Fig. 2; Fig. 7 is a viewtaken on line 7--7 of Fig. 2;

Fig. 8 is a view taken on line 8-8 of Fig. 2;

Fig. 9 is a view taken on line 9-9 of Fig. 1; and ,Fig; 10 illustrates amodification in which the brackets may have integral angular portionsfor mounting the same upon the board instead of the means indicated inFig. l and other figures of the drawings.

It is to be understood that the present formof disclosure is merely forthe purpose of illustration and that there might be'devised variousmodifications thereof without departing from the spirit of my inventionas herein set forth and claimed. t

Referring now to the accompanying drawings in detail, the board 1 hasruled thereupon the usual vertical and horizontal lines 2 and also theradiating lines 3 for the purpose of facilitating the positioning of thepaper or other sheet material thereupon for the trimming operation,either at a right angle or other angles indicated upon the board. Thelines 3 radiate at different angles from a point approximately midway ofthe length of the edge of the shearing blade 8. The scale 3a extendsalong one edge of the board 1 and there is the adjustable slid- .ablymounted stop 4 which extends about the top and two sides of the scale 3aand has a flat spring 4a for releasably holding the same in position towhich it is set for repetitive use when it is desired to trim asuccession of sheets to the same extent. As indicated in Fig. 9 of thedrawings, the lower edge of this stop and its spring 4a may extendslightly beneath the corresponding edge portions of the scale 3a if sodesired. Thetransparent strip 5 is hinged at 511 to the stop 4 so as topermit the same to be swung upwardly and then lowered upon the A workto, be trimmed. The strip 5 has longitudinally marked thereupon a hairline 5b for sighting alignment of the same with a mark on a drawing orother work therebeneath, this strip and its mark 5b being parallel withthe edge of the shear blade 8. The strip 5 may have a scale markedthereupon and may be detachable from the stop 4 which may be employedeither with or without the strip 5.

The rod 6, which may be of square cross section, is inserted within andalong the edge portion of the board 1 and is accurately positioned withrespect to the top surface of the same; and each end portion of this rodis rounded down and screw-threaded, as indicated at 6a, so as to'extendthrough the bracketarm 7a and to receive the screw-threaded nut 11 foranchoring the bracket arms 7a to the inserted member 6, thereby ensuringfixed and dependable position of the same in spite of the fact that theboard 1 may be of wood or other fibrous material. Thus there may beensured accurate positioning of the shear blade and also properpositioning of the brackets 7 and the rails for the reciprocatorycarriage of shear blades; and, when the rod 6 is in place, the shearblade 8 may be screws 12.

Furthermore, each bracket arm 7:: is provided near its applied theretoby means of the machine end with a sized and reamed hole into which isdriven the tubular metal anchor 9 with its leading edge beveled andsharpened so as to enter the wood of the board 1. In each instance themetal anchor 9 will receive the WOOd screw 10 for further securing theend of the bracket arm 71: to the board 1. As will be observed,referring to Fig. 5 of the drawings, the hole through the tubular anchor9 iS'over-size as compared with the size of the screw 10; the idea beingthat if the screw follows the grain of the wood, this will not affectthe position of thebracket arm 7a, as would occur except for the presentprovision. In actual assembling of this device, the holes in thebrackets 7, which receive the ends of the rails 13 and 14 for supportingthe same, will be made to occupy position in a true vertical plane withrelation to the top surface of the board 1, the'nut 11 being onlypartially tightened during this preliminary procedure. Then, when 4front end portion of the spindle 31 has the flanged oilimpregnated orself'oiling bearing 33 for mounting the same in the wall of the carriage16. The inside of the spindle 31 is formed with an annular shoulderagainst which the coil spring 34 may seat; and the rounded-end steelplunger 35 extends within the rear end portion of the proper assemblyhas been obtained, the nut 11 will be ful'ly'tightened' and the tubularmember 9 will be driven into the board, as above referred to, and thewoodscrew 10 will then be driven through the anchor member 9 for stillfurther security. Thus there is ensured the correct position of therails with respect to the top surface of the board and the cutting edgeof the shear blade.

The shear blade 8 is made of flat rectangular form and has four sharpground longitudinal edges, all of which may be employed successively forthe shearing operation; and, for this purpose, the holes through theblade 8 may be positioned midway between the two longitudinal edges andmay be equi-spaced-from the ends of the blade and from each other. Thusthis blade is reversible and its position may be changed with a screwdriver.

To recapitulate briefly, the rod 6 has fixed position and serves toposition the brackets 7 which, in turn, serve to position the rails, andthe rails position the reciprocatory carriage for the rotary cutter.

As already indicated, the two parallel rails 13 and 14 have their endsmounted in the upright portions 7b of the brackets; and the lower one ofthese two rails is provided with a rack 15 along the underside thereof.These rails are adapted to support the carriage 16 for straight linemovement thcrealong,-together with the rotary cutter 17 which is mountedupon the carriage. This carriage 16 comprises the two spaced parallelfront and rear walls 18 and 19, respectively, between which there aremounted the pairs of ball bearings 20 and 21 for operativeengagement-with the upper and lower sides of the upper rail 13; Eachball bearing is pressed onto the middle knurled portion of a spindlewhich'is formed with the integral spacing shoulder 22 and which has aspacing collar 23 pressed onto the same after the ball hearing has beenplaced upon the spindle; and each spindle is screwthre'aded in its twoends for the screws 24 which hold the spindle in each instance betweenthe walls 18 and 19 of the carriage. The screws 24 of the upper pair ofball bearing assemblies serve also as a means for holding thesubstantially rectangular cover member 25 over the top of the carriagewalls 18 and 1S; and this cover member may have applied thereto thehandle member 26 by which the operator may grip the carriage for movingthe same along the rails.

-Meshing with the rack 15 there is the reversing gear 26 which meshesalso with the gear 27 for driving the same as the carriage is movedalong the rails 13 and 14, the idea being to have the cutter rotate inthe corresponding direction of the carriage movement during itsoperation. The reversing gear 26 is pressed tightly onto the' knurledmiddle part of the spindle 28 which is provided with oil-impregnated orselfoiling bearings 29 at its two ends and-with the spacing collars 30betweenthe inner flanges of the bearings 29 and the gear 26 so as tocenter the same within the carriage 16. V

The gear 27 is pressed tightly onto the knurled middle part of thehollow spindle 31 which has its front end screw-threaded to, receive thescrew 32 which, with its washer, hoids the cutter disk 17 in assembly,as clearly indicated in Fig.- 7 of the accompanying drawings. The

the hollow spindle 31 and has its inner end engaged by the coil spring34 while its other end engages against the inner surface of the end ofthe brass cap member 36 which fits'tightly within an opening through thewall 19 of the carriage 16' and which has its inner end flanged forengagement with the inner surface of the wall 19. Between the spindle 31and the cap member 36 there is provided the oil-impregnated orself-oiling bearing 37 which may be of sufficient extent to serve as ameans for centering the gear 27 together with the integrally formedenlarged shoulder portion 31a of the spindle 31. As will be observedfrom Fig. 7 of the present drawings, the arrangement of the plunger35and spring 34 will supply suitable tension to ensure proper engagementof the cutter disk 17 against'the shear blade 8 for the trimmingoperation.

A guard 170 may be provided for the cutter disk 17 and may be mounteduponthe wall 18 of the carriage 16.

Depending upon the size of the device, it may be desirable to provide anauxiliary means of support for the carriage 16 so as to relieve the loadupon the upper rail 13; and, with this in mind, I have indicated theball bearing 38 which is mounted at a point midway between the lowerball bearings 21, located directly below the upper ball bearings 20, andwhich has bearing engagement upon the lower rail 14,

the corresponding edges of the lower parts of the gooseneck portions areflush with the top surface of the board 1 so that it is possibletomoveastrip of sheet material lengthwise of the shearing blade'and tocut from the strip a maximum width corresponding to the depth of thegoose-neck; and furthermore there is obtaineda virtual extension of theboard lengthwise of the shear blade. In this way I am able to increasethe utility of the trimmer and also its cutting capacity withoutincreasing the size of the board 1 itself.

Now I will describe a modified means for mounting the brackets upon theboard, attention being called to Fig. 10 of the present drawings. Inthis modification each bracket is provided with an integrally formedangular portion 40 which engages the corner portion of the board 1 andis countersunk so asto be flush with the top surface of the board, aswell as the edge portion thereof. Thus the angular portion will notinterfere with the location of the scale 3a and will serve as a 'meansof accurately-positioning the bracket, in each instance, for the rails.In case the board he made of wood or other fibrous material, the insertrod 6 may be provided for mounting-the shear blade, as above described.However, the member 9 may be omitted, as also the threaded end 6a of therod, if so desired, in each instance. The angular portions .40 may bescrewed to the board 1' and the fixed predetermined position of theseangular portions will ensure accurate vertical positioning of thebrackets and hence accurate vertical alignment of the rails 13 and 14.These bracket and their angular portions, in each instance, may beformed as a one-piece metal stamping.

Instead of making the board of wood or other fibrous material, it may bemade of metal; in which event the insert rod 6 may be omitted and theshear blade may be applied directly and accurately to the edge of theboard by means of machine screws. In this case the edge of the boardwould be machined and the holes for the shear blade-would be drilled andtapped accurately for machine screws. Also, in the case of a metalboard, the tubular anchor members 9 will be omitted and the angularportions 40 will have accurate countersunk engagement upon the board, asabove described, so as to properly position the brackets for the rails13 and 14.

There are numerous advantages which result from my present invention.For instance, in adopting my means for mounting the shear blade upon awooden board, there may be eliminated the inaccuracy and difiicultywhich would otherwise be experienced because of the natural tendency ofthe screws to follow the grain of the Wood, this improvement includingalso the fixed predetermined mounting of the brackets. I have devised ameans for accurately mounting the brackets in the case of a metal boardalso. In both instances, this means accurate positioning of the railsupon which is mounted the cutter carriage. This assembly is furtherimproved in both efliciency and economy by the provision of a shearingblade with four shearing edges which may be employed in succession byreadily changing the position of the blade. The adjustable stop and itsmeans for holding the same in adjusted position constitutes anotherimprovement, as do also the transparent scale associated therewith, andthe ruling of the board with radiating lines as well as horizontal andvertical lines for positioning the sheet material for shearing atdilferent angles. Other improvements in my present device reside in theparticular means for mounting the ball bearings and the two gears.within the cutter carriage, and also the means for distributing theload of the carriage upon the rails. Furthermore, by means of thegoose-neck form and arrangement of the brackets at the two ends of theshear blade, it is possible not only to trim a certain width from astrip of sheet material up to the depth of the goose-necks by advancingthe same along the shear blade between successive shearing operations,but also the capacity of the trimming board is virtually increased in'adirection lengthwise of the shear blade without having to increase thesize of the board itself. In this invention it will be noted that theupper surface of the lower part of each goose-neck is flush with theupper surface of the board itself, and the diverging form andarrangement of the goose-neck brackets permit the carriage with thecutter to be moved along the shear blade farther in both direc tions.Thus I have devised a trimmer which is capable of operating in a mostaccurate, efiicient, dependable and convenient manner and whichpossesses improvements not heretofore found in other devices of thissame general type, so far as I am aware.

WhatIclaim is:

1. A trimmer comprising a board of fibrous material, a metal rodinserted within the edge of said board, brackets at the two ends of saidinserted rod, said brackets having means for anchoring the same to saidslidably mounted upon said rail means, a rotatable cutter mounted uponsaid carriage and being adapted for up erative engagement with thecuttingedge of said shear blade. J

2. A trimmer comprising a board of fibrous material, a metal rodinserted within the edge of said board and having screw-threaded endportions, brackets at the two ends of said inserted rod, said bracketshaving means for anchoring the same to said board and for securing thesame to said screw-threaded ends of said inserted rod, a shear blade ofmetal fixedly mounted upon said inserted rod, rail means mounted uponsaid brackets and extending parallel to the edge of said shear blade, acarriage slidably mounted upon said rail means, a rotatable cuttermounted upon said carriage and being adapted for operative engagementwiththe cutting edge of said shear blade.

3. A trimmer comprising a board of fibrous material, a metal rodinserted within the edge of said board and having screw-threaded endportions, brackets at the two ends of said inserted rod, each of saidbrackets having a rearwardly extending portion, the opposite edges ofsaid board each having a hole therein, the rear end portion of eachbracket having a tubular metal anchor member attached thereto and ascrew extending through said anchor member for securing the same inposition within said hole in said board, the opening through said metalanchor member being over-size as compared with thesize of the screwtherethrough, each of said brackets having also means for securingengagement between the same and said screw-threaded ends of saidinserted rod, a shear blade of metal fixedly mounted upon said' insertedrod, rail means mounted upon said brackets and extending parallel to theedge of said shear blade, a carriage slidably mounted upon said railmeans, a rotatable cutter mounted upon said carriage and being adaptedfor operative engagement with the cutting edge of said shear blade.

References Cited in the file of this patent UNITED STATES PATENTS1,035,525 Bright Aug, 13, 1912 1,161,774 Johnson et al Nov. 23, 19151,434,475 Austin Nov. 7, 1922 1,612,390 Maynard Dec. 28, 1926 1,623,167Christiansen Apr. 5, 1927 2,223,342 Fehse Dec. 3, 1940 2,327,223 SilverAug. 17, 1943 2,386,652 Borg Oct. 9, 1945 2,459,101 Uhrmacher Jan. 11,1949 2,460,205 Webster Ian. 25, 1949 2,477,295 Garwood July 26, 19492,582,933 Nielson Jan. 15, 1952 2,626,665 Chamberlain Ian. 27, 1953FOREIGN PATENTS 29,136 Great Britain Dec. 18, 1912

